The present disclosure herein relates to a power harvesting system, and more particularly, to a multi-input power manager.
As electronic devices get smaller these days, the life or capacity of batteries included in the electronic devices becomes an issue. An energy harvesting power conversion system is being developed recently in order to address the issue. The energy harvesting power conversion system is used in various small-device or low-power application environments such as a wireless sensor network, for the purpose of implementing battery-less system or battery-powered system with an increased battery life. In the energy harvesting power conversion system, the maximum output power is one of the biggest issues. Accordingly, a maximum power point tracking (MPPT) technology is used to continuously transfer the energy needed in a load, store maximum energy in an energy storage device, or to maximize an energy capacity which can be supplied.
Particularly, a multi-input source structure receives energy from a plurality of energy sources, and high power may thus be output when the energy from each of the plurality of energy sources is added up. In order to simultaneously output the energy received from the energy sources, however, separate power conversion devices are required for each energy source. Since the separate power conversion devices require large areas, it is difficult to apply the multi-input source structure to a small device.